Safety cranking device for gas-engines



M. E, ANDERSON.

SAFETY CRANKING DEVICE FOR GAS ENGINES. APPLICATION FILED Auegle, 1920.

I 1 369,952, Patented Mar. 1, 1921.

, NITE S W arise.

MARTIN E. ANDERSON, or 'rAKo A PARK, MARYLAND;

SAFETY CRANKINGDEVICE FOR GAS-ENGINES. 7

Specification of Letters Patent.

Patented Mar; 1 1921..

Application filed August 19, 1920. Serial No. 404,625. f,

T 0 aZZ whom it may concern Be it known that I, MARTIN E. ANnnnsoN, a citizen of the United States, residing at Takoma Park, in the county of Montgomery and State of Maryland, have invented character, which, in the event ofthe engine back firing while being cranked, will automatically disconnect the crank handle and positively prevent it from rotating backwardly to any considerable extent, thus preventing injury to the operator. i

The invention consists of the features of construction, combination and arrangement of parts hereinafter fully described and claimed, reference being had to the accompanying drawing, in which Figure 1 is a side elevation of the device partly broken away. r

Fig. 2 is an end elevation taken on line A-A, Fig. 1. e V

Fig. 3 is a fragmentary vside elevation partly in section showing the relation of the parts after the device has operated, and

Fig. 4 is a front'view of an automobile showing how the device is attached thereto;

Referring to the drawingyl represents a v stationary hearing, which may be part of the engine frameor part of the frame work of an automobile; slidably and rotatably mounted in bearing 1 is a shaft 2 provided at one end with the usualratchet member 3 for engaging the crank shaftof the engine. Near the other end of the shaft and rigidly connected thereto is a disk like member 4 having a flange5, through which flange and the shaft 2 there passes a pin 6. The disk 4 may, of course, be rigidly secured to the shaft 2 by any other suitable means. The

disk 4 is provided with one or more hol'es 7 for a purpose to be hereinafter described. On the end of the shaft 2 which projects beyondthe flat surface of disk 4 is rotatably and slidab y mounted a ratchet driving member 8 having a hub 9 and a number of peripheral ratchet teeth 10 provided with beveled portions 11. Secured to the hub 9 is a crank 12 of any desired shape. The ratchet disk and crank are resiliently secured in place on the shaft 2 by means one end of which is secured to the crank by of a spring 13,- I

means of screws 14 while the other end passes through an opening 15 in hub 9, and engages Wlth an annular groove 16 in the end of shaft 2. The tension in spring 13 tends to force the flat face of theratchet member against the corresponding surface of d1sk4. Carriedby the ratchet 8 is one or morepins 17 arranged to engage'with the openings 7 indisk 4. Rotatablysecuredto the disk 4 by means ofthe overhanging hook like portion 18 and plate 19is aplate 20; this plate has a downwardly projecting portion 21 whose surfacelies substantially in the plane of the front surface of disk 4.

Carried by the portion 21 and pivotally connected thereto by means of a rivet 22is a pawl 23 having a wedge'shaped point 24 terminating in a stop or projectingportion 25. The pawl 23 isresilientlyheld against the ratchet teeth 10 by means of a spring 26,secured to the pawl and downwardly projecting portion in the manner shown- To prevent the plate 20 from rotating it' is anchored to the stationary parts of the framework of the engine or automobile by some suitable means. In the drawing-I have shown a rod 27 as performing this function, one'end being secured to the downwardly projecting portion 21 and the other .to the framework of the. automobile in the manner indicated in Fig. 4. r Y

ju'sted by means of the screws 14in a manner which is apparent from the drawing,

The operation of the device is as-follows: The crank-handleis grasped and'the'shaft 2 shoved toward the engine until; the ratchet 3 engages with the coo'per ating pin in the crank shaft and then the. necessary force is applied to. turn the engine). The pawl 23 will permit the ratchet teeth 10 to rotate freely in a clockwise direction, but "incase the ignition point should be' too far-advanced and the explosion take placeat such a time that the engine would tendyto movefin a counter-clock-wise direction, the ratchet teeth 10 will move toward the-point 24; of

the pawl 23 and thencontinue to ride-up the'inclined surface of the pawl {until "the ratchet member 8. becomes separated, from the disk 4 a sufficient distance to permitthe pin or pins 17 to disengage the openings 7 and'thus disconnect the crank from the ro- The tension of the spring 13 canfbe., adv s tating disk 4. When the tooth 10 has moved up the inclined surface of the pawlthe distance required to withdraw the pin 17 from 'firing" of the engine is entirely removed.

There will, of course, be a slight reverse movementof'the crank handle as it 1s necessary that it move counterclock-wise through a sufficient arc to allow the pawl to accomplish the necessary disconnection, but

the crank cannot continue in its reverse rotation because it encounters the stop 25.

The cranking device is shown attached to an automobile, in Fig. at, but it is as well adapted to be used with any explosive engine, and it should especially be employed in connection with tractor engines and on trucks, where the operator is obliged to employ both his. hands and all his strength to turn the engine.

Since the cranking device shown and described is a unitary structure, it can be used as well on cars where the crank isremoved from the front of the machine, as on those cars having'thecrank permanently attached thereto, the only requirement being that the disk 20 be anchored to the framework so as to prevent rotation.

I am aware that similar devices have been invented and patented, and I do not claim the idea in its broadest aspect, but I do desire protection for such features of construc. tion as are not present'in the prior art and which distinguishes my invention there from'.;

I claim as my inV'ention- 1. A driven member comprising a shaft, a circular, disk secured thereto; said disk beingprovided with one or more openings, a drivlng member rotatably and longitudinally movable with respect to said disk; re-

silient means for causing said driving memher to engage the surface of said disk, means carried by said driving member for engaging the openingsin said disk and for preventing relative rotation of the disk and driving member, a plate rotatably connected to said disk, a pawl pivotally attached to said plate and engaging the surface of said disk, ratchet' teeth on the peripheral sur faceof said driving member, resilient means for forcing said pawl into contact with said ratchet teeth, means for. preventing the rotation of said plate and pawl, and means on said pawl for disconnecting the driving member from the disk and permitting rela disk near the other end of said shaft and non-rotatably connected thereto, a driving member rotatably and slidably connected to the end of the shaft projecting beyond said disk, resilient yielding means for securing said driving member'to said'shaft and for forcing said driving member toward the face of said disk, openings, in said disk, and means on said driving member engaging with said openings to prevent relativerotation of said disk and driving member, a series of ratchet teeth around the periphery of said driving member, a pawl pivotally connected to said plate, and lying against the surface of said disk, resilient means attached to said pawl and plate whereby said pawl is held against the ratchet teeth of the driving-member, means for preventing ro-' tation of said plate and means comprising said pawl and ratchet teeth for disconnecting the driving member from the disk whenever the driving member is forced to rotate in the reverse direction.

3. A driven member, a circular disk nonrotatably secured thereto, said disk being provided with one or more openings, a driving member rotatably and slidably 'at tached to said disk, resilient means for causing said driving member to engage the surface of said disk, means carried by said driving member for engaging the openings in said disk to prevent relative rotation of the driving member and disk, a plate rotatably connected to said disk a pawl pivot ally attached to said plate and extending over the face of said disk, said pawl being provided with wedge shaped point, ratchet teeth on the peripheralsurface' of said driving member, resilient means for forcing said pawl against said ratchet teeth, means for reventinv the rotation of said late and pawl, whereby the wedge shaped point of saidpawl will be forced between the disk and the driving member upon reverse rota? tion of the latter for the purpose. of separating the driving member from the disk with a beveled portion In testimony whereof I have my signature, v a p MARTIN E. ANDERSOhh 

